testing-guide

# VibeCode Testing Guide ## Framework - Jest with ts-jest transform - Test files: `*.test.ts`, `*.test.tsx` - Locations: `tests/unit/`, `tests/integration/`, `tests/` ## Running Tests ```bash # Full suite (ALWAYS use --maxWorkers=2) npx jest --maxWorkers=2 --passWithNoTests # Single file npx jest --maxWorkers=2 path/to/file.test.ts # With coverage npx jest --maxWorkers=2 --coverage # Pattern match npx jest --maxWorkers=2 --testPathPattern="auth" ``` ## Test Patterns ```typescript import { describe, it, expect, jest, beforeEach } from '@jest/globals'; describe('ModuleName', () => { beforeEach(() => { jest.clearAllMocks(); }); describe('functionName', () => { it('should handle normal input correctly', () => { // arrange, act, assert }); it('should throw on invalid input', () => { expect(() => fn(null)).toThrow(); }); }); }); ``` ## Mock Patterns - Mock next-auth: `jest.mock('next-auth', () => ({ getServerSession: jest.fn() }))` - Mock prisma: `jest.mock('@/lib/prisma', () => ({ prisma: { user: { findUnique: jest.fn() } } }))` - Mock env vars: `process.env.X = 'value'` in beforeEach, cleanup in afterEach - Mock fetch: `global.fetch = jest.fn().mockResolvedValue({ json: () => ({}) })` ## Known Pre-Existing Failures (do NOT fix, do NOT block on) - `tests/feature-audit/issue-1527.test.ts` - `tests/unit/components/AppNavigation.test.tsx` - `tests/unit/lib/auth-password.test.ts` (2 failures) - Several page-level tests with route-metrics issues ## Critical Rules - NEVER use `--maxWorkers` > 2 (OOM, exit 137) - NEVER delete tests to make suite pass - After deleting source files, grep for orphaned test imports - Mock external dependencies, never make real API/DB calls